He added that the firm had "the courage to do the right thing", but questioned whether ten per cent was enough and why the move was "limited to gas alone".
Mr Mayo stated there was one "underlying fault" in the energy market which regulator Ofgem needs to take a stand on.
"Consumers would not have to rely on occasional grand gestures by energy companies if the market was more transparent and competitive in the link between wholesale and retail prices," he said.
Consumer Focus recently welcomed a new private members' bill put forward by David Heath MP which called for homes to be made more "fuel poverty proof".
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